（灵枢论痛篇）
黄帝问于少俞曰∶筋骨之强弱，肌肉之坚脆，皮肤之浓薄，腠理之疏密，各不同，其于针石火 之痛何如？肠胃之
浓薄坚脆亦不等，其于毒药何如？愿尽闻之。（ ，火 也，灸灼之类。毒药，谓药之峻利者。人有能胜毒者，有不能胜
毒者，义见末节。 ，如税切。）少俞曰∶人之骨强筋弱、肉缓皮肤浓者耐痛，其于针石之痛、火 亦然。黄帝曰∶其耐
火者，何以知之？少俞答曰∶加以黑色而美骨者，耐火 。黄帝曰∶其不耐针石之痛者，何以知之？少俞曰∶坚肉薄
皮者，不耐针石之痛，于火 亦然。（美骨者，骨强之谓。砭，音边，石针也。）黄帝曰∶人之病，或同时而伤，或易已，
或难已，其故何如？少俞曰∶同时而伤，其身多热者易已，多寒者难已。（此皆指外邪致病为言也。多热者病在阳分，故
易已；多寒者病在阴分，故难已。）黄帝曰∶人之胜毒，何以知之？少俞曰∶胃浓色黑、大骨及肥者，皆胜毒；故其瘦而
薄胃者，皆不胜毒也。（胃浓者脏坚，色黑者表固，骨大者体强，肉肥者血盛，故能胜峻毒之物。若肉瘦而胃薄者，气血
本属不足，安能胜毒药也。胜，平声。）
（素问五脏别论）
黄帝问曰∶余闻方士，或以脑髓为脏，或以肠胃为脏，或以为腑，敢谓更相反，皆自谓是，不知其道，愿闻其说。（方
士，谓明悟方术之士。脏腑之称，异同不一，故欲辨正之也。即在本经亦有之矣，如灵兰秘典论曰∶愿闻十二脏之相使。
六节藏象论曰∶凡十一脏取决于胆也。是亦此类。）岐伯对曰∶脑髓骨脉胆女子胞，此六者地气之所生也，皆藏于阴而象
于地，故藏而不泻，名曰奇恒之府。（凡此六者，原非六腑之数，以其藏蓄阴精，故曰地气所生，皆称为腑。然胆居六腑
之一，独其藏而不泻，与他腑之传化者为异。女子之胞，子宫是也，亦以出纳精气而成胎孕者为奇。故此六者，均称为
奇恒之府。奇，异也。恒，常也。胞音包。）夫胃大肠小肠三焦膀胱，此五者天气之所生也，其气象天，故泻而不藏，此
受五脏浊气，名曰传化之府，此不能久留输泻者也。（凡此五者，是名六腑，胆称奇恒，则此惟五矣。若此五腑，包藏诸
物而属阳，故曰天气所生；传化浊气而不留，故曰泻而不藏；因其转输运动，故曰象天之气。）魄门亦为五脏使，水谷不
得久藏。（魄门，肛门也。大肠与肺为表里，肺藏魄而主气，肛门失守则气陷而神去，故曰魄门。不独是也，虽诸腑糟粕
固由其泻，而脏气升降亦赖以调，故亦为五脏使。）所谓五脏者，藏精气而不泻也，故满而不能实。六腑者，传化物而不
藏，故实而不能满也。（五脏主藏精气，六腑主传化物。精气质清，藏而不泻，故但有充满而无所积实；水谷质浊，传化
不藏，故虽有积实而不能充满。）所以然者，水谷入口，则胃实而肠虚；（食未下也。）食下，则肠实而胃虚。（水谷下也。）
故曰实而不满，满而不实也。
(Ling Shu: Lun Tong Chapter)
Huangdi asked Shaoyu, "The strength of sinews and bones, the firmness or fragility of muscles, the thickness of skin, and the density of interstitial spaces (Cou Li) vary among individuals. How do these differences affect their tolerance to pain from acupuncture stones and moxibustion? The thickness and firmness of the stomach and intestines also differ; how does this affect their tolerance to toxic medicines? I wish to hear the complete explanation." ("Bian" refers to stone needles or similar tools; "Jiu" refers to moxibustion burning. 'Toxic drugs' refer to medicines with harsh and potent properties. Some people can withstand toxicity, while others cannot; the meaning is explained in the following section. 'Bian' is pronounced like 'Shui'.)
Shaoyu replied, "Individuals with strong bones, weak sinews, relaxed muscles, and thick skin are tolerant to pain. They are also tolerant to the pain of acupuncture stones and moxibustion."
Huangdi asked, "How can one identify those who are tolerant to moxibustion?"
Shaoyu answered, "Those with dark complexion and well-formed bones are tolerant to moxibustion."
Huangdi asked, "How can one identify those who are not tolerant to the pain of acupuncture stones?"
Shaoyu said, "Those with firm muscles and thin skin are not tolerant to the pain of acupuncture stones, nor are they tolerant to moxibustion pain." ('Well-formed bones' refers to strong bones. 'Bian' is pronounced 'Bian', referring to a stone needle.)
Huangdi asked, "When people fall ill simultaneously, some recover easily, while others find it difficult. What is the reason for this?"
Shaoyu replied, "When injured by pathogens at the same time, those with more heat symptoms recover easily, while those with more cold symptoms find it difficult to recover." (This refers to diseases caused by external pathogens. Heat indicates the disease is in the Yang aspect, hence easy to recover; cold indicates the disease is in the Yin aspect, hence difficult to recover.)
Huangdi asked, "How can one determine who can tolerate toxic medicines and who cannot?"
Shaoyu replied, "Those with robust stomach Qi, dark complexion, large bone structures, and obesity can all tolerate toxic medicines. Conversely, those who are emaciated and have thin stomach walls cannot tolerate them." (Robust stomach Qi implies solid internal organs; dark complexion implies secure exterior; large bones imply strong constitution; plump flesh implies abundant blood. Thus, they can withstand harsh drugs. If flesh is emaciated and stomach Qi is thin, both Qi and Blood are inherently deficient, so how could they withstand toxic medicines? 'Sheng' is pronounced with the level tone.)
(Su Wen: Wu Zang Bie Lun Chapter)
Huangdi asked, "I have heard that some scholars of medical arts classify the brain and marrow as Zang organs, or the stomach and intestines as Zang organs, or classify them as Fu organs. These views contradict each other, yet each claims correctness. I do not understand the principle behind this and wish to hear your explanation." ('Scholars of medical arts' refers to wise individuals proficient in medical techniques. The terminology for Zang and Fu organs varies, so clarification is desired. Similar instances exist within this text, such as in Ling Lan Mi Dian Lun stating, 'I wish to hear about the mutual governance of the twelve Zang organs,' and Liu Jie Zang Xiang Lun stating, 'All eleven Zang organs depend on the Gallbladder.' These are examples of such classifications.)
Qibo replied, "The brain, marrow, bones, vessels, gallbladder, and uterus (in women) are generated by Earth Qi. They store Yin essence and correspond to the Earth, thus storing but not excreting. They are named the Extraordinary Fu Organs (Qi Heng Zhi Fu)." (These six organs originally do not belong to the category of the Six Fu organs because they store Yin essence, hence called 'generated by Earth Qi' and termed 'Fu'. However, although the Gallbladder is one of the Six Fu organs, it uniquely stores without excreting, differing from other Fu organs that transmit and transform. The uterus, also known as the 'Baopo', is considered extraordinary because it receives and discharges essence to facilitate pregnancy. Therefore, these six are collectively called Extraordinary Fu Organs. 'Qi' means extraordinary or different; 'Heng' means ordinary or constant. 'Bao' is pronounced 'Bao'.)
As for the stomach, large intestine, small intestine, San Jiao (Triple Burner), and bladder, these five are generated by Heaven Qi. Their nature corresponds to Heaven, thus excreting but not storing. They receive turbid Qi from the Five Zang organs and are named the Transmitting and Transforming Fu Organs (Chuan Hua Zhi Fu). These organs cannot retain contents for long but continuously transport and excrete them." (These five are named the Five Fu organs; since the Gallbladder is classified as an Extraordinary Fu organ, only these five remain here. As these five Fu organs contain various substances and belong to Yang, they are said to be generated by Heaven Qi. Because they transmit and transform turbid Qi without retention, they are described as 'excreting but not storing'. Due to their dynamic transport function, they are said to correspond to the Qi of Heaven.)
The anal aperture (Po Men) also serves as an assistant to the Five Zang organs, preventing the prolonged storage of food and water residues. ('Po Men' refers to the anus. The Large Intestine and Lung are exterior-interior paired organs; the Lung stores Po (Corporeal Soul) and governs Qi. If the anus loses its controlling function, Qi sinks and Spirit departs, hence it is called 'Po Men'. This applies not only to the anus; although waste from all Fu organs is indeed expelled through excretion, the ascending and descending movement of Zang Qi also relies on this regulation, making it an assistant to the Five Zang organs.)
The so-called Five Zang organs store Essence and Qi without excreting, thus maintaining fullness but not solidity (accumulation of solids). The Six Fu organs transmit and transform substances without storing, thus achieving solidity (accumulation of solids) but not fullness (of Essence/Qi)." (The Five Zang primarily store Essence and Qi, while the Six Fu primarily transmit and transform food substances. Essence and Qi are clear and pure, stored without excretion, resulting in fullness without accumulation of solids; food and water are turbid, transmitted and transformed without storage, resulting in accumulation of solids but not fullness of Essence/Qi.)
This is why, when food and water enter the mouth, the stomach becomes solid (filled with food) while the intestines are empty; after digestion, the intestines become solid (filled with residue) while the stomach becomes empty. Therefore, it is said that the Six Fu are 'solid but not full', and the Five Zang are 'full but not solid'.